I respectfully disagree, you can pint on bare drywall no problem. See my answer.
–
mohlsenMay 18 '12 at 16:31

1

You should definitely prime the walls first. The mud joints soak up the paint and it would take several coats over any mudded area to look uniform with the rest of the walls. Do yourself a favor. Don't listen to these guys that are flipping houses. They are out to make a quick buck. Do it right by priming the walls. Better yet, try your own experiment. You'll see Conor Boyd and I are correct.
–
user20530Mar 19 '14 at 0:02

For what it's worth, the "paint plus primer" paints seem to vary in their ability to actually cover the drywall. In my experience the darker/stronger colors need tinted primer or else you end up with 4 coats of "paint plus primer" to get the coverage you need. In other words: use a good primer and save yourself some extra money on your paint.
–
ClayMar 19 '14 at 13:53

In the UK, you don’t need to prime bare drywall or plaster before painting with normal emulsion paint. However the first coat will soak in and you will need a few more coats. (If you are using a very high spec paint that is thicker you may find that the first coat does not stick well without a mist coat, but I would always use a cheap paint for the first coat anyway.)

The normal advice is to use cheap MATT emulsion paint, watered down a bit, for the first coat as this will act as a sealer. Also if the plaster has been polished and is very smooth give it a quick light sanding will help any paint to stick well.

You do not need to use a Primer on bare drywall. I have painted numerous new houses, including mine, over the last 10 years and never have I primed the bare drywall. No issues what so ever. 2 coats of any good latex paint will be fine, no question.

If you were going to be painting over existing paint, it would certainly help and can save an extra coat or two of the new color. Also a good thing if you are painting over a wall that had wallpaper removed. Also good if you are paining on really old walls that are extremely dry and may soak up a lot of paint. But it doesn't sound like any of that applies to you.

People will argue that Primer is cheaper than good paint, so use the primer and save a coat of the expensive stuff. I can see that argument. But in my case, I would rather save time and stick to the same paint, rather than having to clean all the equipment and start over, especially if you are doing it the same day.

For your second question, primer might be a good idea before you mud over the textured / painted walls. Mud sometimes has a hard time sticking to painted surfaces. You could also give it a light sand that would help it stick. We reciently had to have our ceiling redone, and the drywaller had concerns about it sticking. Rather than priming it, he did a light sand, then used DuraBond to mud the ceiling rather than standard joint coumpound. DuraBond supposedly makes a better bond, seals out moisture/humidity, and reduce cracks/blemishes over standard compound.

Well you don't need to do anything -- in fact you don't need to put drywall up but you should prime drywall if you want a better finish on the wall. It seals the paper and seams. You often see a color variation or see the seams if you don't seal the wall. Sealing with a primer makes the whole wall the same surface that the paint can adhere to giving you a more uniform look. Have you ever gotten really close to a wall and looked down the side and you could tell where the seams were? They probably didn't use a primer.

weve prepcoated drywall.and even putty coated drywall.and checkout with a 500 watt light.sideways on the dry wall.to show all defects.and still primed the walls.or the paint can burn though your prep coat.and you will still half to paint again.or spray more prep coat.always use a good primer.